Reserve for Future Policy Benefits and Contractholder Funds - Schedule of key assumptions used in calculating the reserve for future policy benefits (Details)	Mar. 31, 2023	Mar. 31, 2022
Accident and health insurance
Liability for Future Policy Benefit, Activity [Line Items]
Weighted-average duration (in years)	4 years 1 month 6 days	4 years 2 months 12 days
Interest accretion rate (discount rate at contract issuance)	5.09%	6.69%
Current discount rate (upper-medium grade fixed income yield)	458.00%	276.00%
Traditional life
Liability for Future Policy Benefit, Activity [Line Items]
Weighted-average duration (in years)	14 years 1 month 6 days	13 years 10 months 24 days
Interest accretion rate (discount rate at contract issuance)	5.50%	5.70%
Current discount rate (upper-medium grade fixed income yield)	503.00%	354.00%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Current weighted-average discount rate used to measure liability for future policy benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
-Paragraph 6
-Subparagraph (b)(6)
-URI https://asc.fasb.org/extlink&oid=124506351&loc=d3e14931-158439

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 55
-Paragraph 29E
-URI https://asc.fasb.org/extlink&oid=126561865&loc=SL117819541-158441

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- Definition

Weighted-average duration of liability for future policy benefit, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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Original weighted-average discount rate at contract issue date used to measure liability for future policy benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 55
-Paragraph 29E
-URI https://asc.fasb.org/extlink&oid=126561865&loc=SL117819541-158441

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
-Paragraph 6
-Subparagraph (b)(6)
-URI https://asc.fasb.org/extlink&oid=124506351&loc=d3e14931-158439

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